Ultraviolet absorption spectroscopy

Abstract

Conclusions In a single lecture on a subject as big as ultraviolet absorption spectroscopy as applied to fats and oils, the contributions of many, many workers cannot even be mentioned. most of the techniques and much of the mass of useful data which have been accumulated represent contributions from scores of research workers. in this lecture only a few have been cited as examples of what ultraviolet absorption spectroscopy can do—what it is doing for the fat and oil chemist. As one hears more about newer techniques in spectroscopy, infrared absorption, microwave spectroscopy, nuclear magnetic resonance spectroscopy, etc., he is likely to think of ultraviolet absorption as an older technique which has probably made its contribution and is now to be relegated to “classical methods.” Nothing could be further from the actual picture today. As newer techniques open up a greater understanding of the chemistry of fats and oils, of their constitution, of the mechanisms of their chemical reactions, ultraviolet absorption spectroscopy will be called upon to make on ever‐increasing contribution. Newer techniques to obtain pure components, such as improved chromatography, countercurrent distribution separations, etc., will also make greater and greater demands upon the use of ultraviolet absorption spectra. As long as fatty acid chemistry deals with constituents which either contain conjugated unsaturation, or unsaturated linkages which can be conjugated, either accidentally or by design, ultraviolet absorption spectroscopy will remain its most valuable tool.

Solution-assisted ultrafast transfer of graphene-based thin films for solar cells and humidity sensors

“…The different hydrogen bond strengths cause different energies for electronic transitions, leading to a diverse ultraviolet absorption spectrum. Based on equation (1) [23]:…”

Reaction of 3‐methyl phenol with methyl α‐eleostearate

“…Phenols are addition-reacted with tung oil via the conjugated triene structure of a-eleostearic acid, the triglyceride of which is the main component of tung oil, and then reacted with formaldehyde on the phenolic nucleus to yield flexible phenolic resins. A number of papers have reported on the reaction products between tung oil and phenols, but they have reported little on the reactions between tung oil and phenols.2- 20 We reported about the reaction of 3-methyl phenol with tung oil. But we reported nothing but the average structure of the reaction product of 3-methyl phenol with tung oil in its report.…”

Ultraviolet Spectrophotometry

“…In the f elds of oils and resins, in addition to the chapter by Shreve (111), O'Connor has reviewed the applications of spectroscopy to the analysis of oils and fats (89). Swann, Adams, and Weil (118) determined benzoic acid in alkyd resins after separation of fatty and dicarboxylic acids.…”